1. Field of the Invention
The invention relates to a process for forming a curved projection screen. More specifically, the invention relates to a process for forming such a screen from a single, continuous, sheet of material.
The invention also relates to a curved projection screen made in accordance with the inventive method.
2. Description of Prior Art
It is, of course, well known in the art that simulator systems require large display screens as is taught in, for example, U.S. Pat. No. 4,473,355, Pongratz, Sept. 25, 1984. However, the screen as taught in the '355 patent is an inflatable screen. As seen in FIG. 5 of the patent, a screen having a lenticulated surface is contemplated by the Pongratz patent.
U.S. Pat. No. 3,348,897, Hourdiaux, Oct. 24, 1967, teaches a curved projection screen which consists of a plurality of panels 20a to 20d (FIG. 2) held together with screw clamps 26. As is well known, screens made of a plurality of panels provide a certain degree of distortion at the joints between the panels.
U.S. Pat. No. 3,632,185, Meanor, Jan. 4, 1972 teaches a dome-shaped projection screen which is made of three sections which telescope into each other when the screen is not in use. This is illustrated in FIG. 2 of the patent.
A second patent of Hourdiaux, U.S. Pat. No. 3,384,432, May 21, 1968, teaches the connecting together of a plurality of rods to form curved screens.
A curved screen comprising a plurality of abutting panels is illustrated in U.S. Pat. No. 3,992,841, Ward Jr., Nov. 23, 1976. The edges of some of the panels overlap the edges of adjacent panels.
In U.S. Pat. No. 3,998,522, Holzel, Dec. 21, 1976 and U.S. Pat. No. 4,022,522, Rain, May 10, 1977, curved screens are formed by drawing a vacuum behind a membrane. In both cases, the membrane is supported on a peripheral frame which is enclosed by a back cover. A vacuum is drawn through the back cover whereupon the membrane will take on the shape of the peripheral frame. The main difference between the two patents is in the shapes of the frames. In both of these patents, the membrane must remain attached to the frame in order to maintain its shape.
Both U.S. Pat. No. 4,232,939, Kikuchi, Nov. 11, 1980 and U.S. Pat. No. 4,235,513, Vlahos, Nov. 25, 1980, teach projection screens having a lenticulated surface.
U.S Pat. No. 4,750,807, Chamayou dit Felix, June 14, 1988, teaches a curved screen which is formed from a plurality of triangular elements each of which is curved at the radius of curvature of the screen.
Not all of the patents above-discussed describe the method for making the screens as taught in the patents. However, certainly, none of them teach a method for making a stand-alone screen from a single, continuous, sheet of material.